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Case File

CVE-2021-27256

HIGH · CVSS 8.8 EPSS 0.87% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2021-03-05 · Last synced 2026-08-04

CyberRota Analysis

This is a high severity vulnerability with a CVSS score of 8.8. Public exploit code or proof-of-concept references have been detected in its references.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

Detected Signals
exploit

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2021-27256
Severity
HIGH
CVSS
8.8
EPSS
0.87%

Original NVD Description

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R7800 firmware version 1.0.2.76. Although authentication is required to exploit this vulnerability, the existing authentication mechanism can be bypassed. The specific flaw exists within the handling of the rc_service parameter provided to apply_save.cgi. The issue results from the lack of proper validation of a user-supplied string before using it to execute a system call. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-12355.

Related CVEs

Other vulnerabilities affecting the same vendor(s)